John Carreyrou is an American investigative reporter currently at The New York Times. He previously worked for The Wall Street Journal for 20 years, from 1999 to 2019, during which time he established himself as a prominent investigative journalist. Throughout his career, he has been based in Brussels, Paris, and New York City. Carreyrou is best known for his investigation into Theranos, a multibillion-dollar blood-testing company. His series of articles published in The Wall Street Journal exposed the company's fraudulent practices, bringing significant public attention to the scandal. This work earned him recognition in his field and contributed to his receiving the Pulitzer Prize twice.